I’ve been working with a single sheet of 1/4" Baltic Birch the past couple of days and the consistency is all over the place. I’ve used 1/8" BB from the same source (Rockler) for a couple of years and never had this much of an issue. It’s basically what @deirdrebeth said, it’s full or hollows and voids, even though it’s supposed to be a high grade material.
I’ve used cheap 3/16 Lauan ply (“underlayment”) a lot and never had this much trouble.
When it comes to 1/4" ply, it’s not the machine, it’s the material.
Now if you feel your machine is not cutting Proofgrade correctly, you’ll need to print the Gift of Good Measure on the spare piece of Medium Draftboard that was sent with your machine, and post pics here. Support can then advise.
Edit - I just realized, I should add, I had been using 1/4" hardwood (poplar) for some smaller items over the weekend, and I had no such issue like what I’ve had with the 1/4" ply.
i have given up 1/4 plywood. I would rather cut the part 2 times in 1/8th and glue them together.
I have had such problemes but it has always been something. The lenses are the most usual now. The slightest bit of crud or even smoke being too near one of those windows will screw up the next cut, and it will take an amazingly small amount to do that.
Before I figured out the problems with magnets they were the problem most often. It was extremely frustrating not finding the issues the magnets were creating when I was not aware they could be the problem, eventually wrecking my machine almost at the end of the warranty period.
In order to know what settings will work, I make these and it will show perhaps one setting that barely makes it through and the settings that make it through easier and easier. If I am worried that it is very important for the cut to be clean I might take the second or third one that makes it through. In every case, the outer window of the head is the most prone to collecting a film and cleaning that makes a huge difference in the cleanliness of the cut even if it is a bit overpowered.
As others have noted the material can be a big problem even different places in the same material. The worst I have seen was 1/4 inch birch plywood when even extreme overpowering was no help.
The two 1/4" plywoods I have had the best results with are one called Revolution and the other is Oak plywood though that one needs to be catrfully chosen for fewer knots on the bottom.
Just making sure; are you cleaning the windows too? One over in the left side of the machine, one on the side of the head itself, and one on each side of the lens opening on the bottom of the head? Some folks have missed one or more of those (especially that hidden one in the left side!) and had poor results, so I thought I’d check!
^^^^ What she said! Much less than this will really reduce the ability to cut but will make a burned mess on the top…
I’ll try that. But its with all materials.
I can try that. My concern is it’s all the time with all materials. Same fonts never seem to cut the same even on the same material same setting and same font and same size font. One can come out perfect , one can be charred and broken in some spots, one may cut all the way through except a few spots leaving my project unable to be removed without breaking it. I seriously am just so stressed out. I have to run my business and I have 2 signs to make that are way over due and I cant get this machine to cut the damn fonts out properly. And we all know buying glow gorge materials is 3x the price for me to do it myself. I’m buying A quality Birch plywood. 1/4 inch should not be struggling. What’s worse is I have to tell the glow forge the material is .5 thick just to get it to cut through 1/4 that’s not good. Same for 1/8 I have to lie and put in I’m cutting something thicker or it wont cut through.
There’s part of your problem. You’re diffusing the laser when you do that. It’s an X shape, and the goal is to position the narrowest part of the X at the surface of the material for the highest power on the narrowest area. If you tell it the material is twice as high as it is, you get the wider part of the beam falling on the surface, so the power is spread across a larger area and it won’t cut as deep. So then you bump up your power and end up charring a wide swath of material instead of having a nice clean cut line.
Ack! Yes - what @geek2nurse said. No wonder you are having problems with cuts! Enter the height of the material exactly correctly, or even better use Set Focus*. That, along with inferior materials, could totally explain all your issues. “A quality Birch plywood” is not high quality in any sense except it looks pretty on one side. For lasers the core is as (if not more) important than the exterior. Check in to BB grade baltic birch and you’ll have better results. It’s more expensive, but not quite as expensive as proofgrade - and you’ll have to finish it and add masking.
*I made that exact same error when I first got the machine, but realized the issue when it wouldn’t cut through well. If you want a stronger cut you raise the power or lower the speed - do not change the height unless you’re looking to defocus (get wider/weaker)
Thank you, everyone! I’d like to take a look at a specific print, so that we can create a good baseline for your Glowforge.
Could you please do the following?
- Turn off your Glowforge, then turn it back on
- We included an extra piece of Proofgrade Draftboard with your materials shipment for troubleshooting. Place Proofgrade Draftboard in the bed and load the Gift of Good Measure design.
- Set the score and engrave steps to ‘ignore.’ Print the Gift of Good measure using the default settings. Allow the print to finish.
- When the print finishes, leave the lid closed and wait until the fans stop and the picture of the bed updates.
- Check the completed print:
- If the Gift of Good Measure fails to cut, please let us know the date and time of the print
- If the Gift of Good Measure cuts successfully, please try another print of the design you saw the issue with, and let us know the results.
- If the issue still occurs, please let us know the date and time of the finished print.
Let me know how it goes!
What @geek2nurse and @deirdrebeth said about material height/set focus. That is the first variable to nail down.
The second variable to eliminate is the material composition/density. That is why @Jacob.U is asking you to do only the cut operations on Proofgrade draftboard. That will show whether or not it is actually a material issue or not.
Not sure if you have some thick draftboard or Proofgrade plywood and that would show that it has the power on thicker materials.
I do not see the font as an issue at all, unless there is something in your design that might cause a problem. That would be the last thing. Too many other issues to tackle first.
I have used inexpensive 1/4" plywood of many forms in my Basic Glowforge. It works just great for cheap material but it almost never is a perfect cut. I usually slow it down to make sure, over burning some of it just to keep the voids at a minimum.
That being said, there are 1/4" plywoods that can be reliably cut. Until you do an AB test on some reliable plywood, I would imagine it has to be the material issue. Plus a little more understanding of speed and power and focus and how that works in a cut.
Don’t despair. The Glowforge will work as you intend it too once we get this narrowed down.
long ago I made this same mistake. unlike my milling machine where I sometimes have to lie about material thickness in order to get the bottom to cut to the right depth, the laser will not try harder if you tell it that the part is thicker. to try harder, slow down or use more power or both. .
Okay that helps explain why that may not cut properly. So If I have been using 125 and measure with a caliper the exact thickness then would that cut through? When I did .25 you couldn’t see a line to the back of the board as if it was lasered only a portion way through. Should I do 120 speed? Wouldn’t that char even more?
Thank you. I am using full power. So I will need to try slower .
I use this test strip to dial in my settings. Takes out the guesswork!
Are you entering these numbers in Material Thickness or Focus Height?
Yes, and sometimes it only works when I either char the wood with a super slow setting or increase the thickness. I’ll just keep following tips here and hope I find the best way.
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